The federally owned chimpanzees previously resided at the New Iberia Research Center in Lafayette, Louisiana before being declared permanently ineligble for research in September 2012 by the National Health Institute (NIH).

"An investigation at New Iberia conducted by The HSUS and broadcast by ABC News in 2009 was a pivotal moment in our efforts to end chimpanzee research and retire chimpanzees to sanctuary," Wayne Pacelle, President and CEO of the Humane Society of the United States (HSUS), writes on his blog.

The hidden investigative video taken inside New Iberia provides a shocking glimpse into the psychological stress and heartbreaking living conditions that these great apes suffered through at the large pharmaceutical research lab.

Due to logistical constraints, the NIH originally planned to move just 10 of the New Iberia chimps to the sanctuary while sending the remaining to another laboratory in Texas, but the HSUS and other animal welfare organizations urged the government to instead send all 110 of them to Chimp Haven for a proper, humane retirement.

In order to make this happen, the HSUS partnered with the NIH Foundation to raise $2.3 million in funds for Chimp Haven to construct new chimpanzee housing and play areas, provide humane transportation to the sanctuary and get the chimps settled and integrated into the already existing social groups.

In the video below, we witness the emotional moment when the chimps step out into the sunlight for the first time. Prior to their release, some of the chimps had spent 40-50 years of their lives in metal lab cages. While some of the chimps born in the wild might faintly remember the feel of grass on their palms and soles, many others who were born in captivity have known nothing but the cold, metal surfaces of a laboratory.

Despite this momentous victory, the work is far from done. If you're interested in directly supporting the future care of these remarkable chimpanzees living at Chimp Haven, consider donating to the New Iberia Chimpanzees to Sanctuary Fund. In the meantime, continue below for a heartwarming look at how these chimps are spending the first weeks of their newfound retirement.

A group of chimpanzees enjoys their morning diet inside Chimp Haven's Butler Habitat.

A chimp named Arden plays and swings from ropes tied to trees.

Jimmy and another chimpanzee play around near an enclosure fence.

Leilani Case, an Enrichment Technician working at Chimp Haven, tosses a couple of kong toys into an enclosure for the chimpanzees.

Mason and Jimmy play and wrestle around in the grass.

A young chimp named Diane embraces her mother Muffy.

A chimp named Hillary munches on some fresh greens.

Diane works on her climbing skills as she scales a tree inside her enclosure.